The present invention relates to a push button switch provided with an alternate action mechanism.
Generally, known alternate action mechanisms include a so-called heart cam groove formed in the manipulation lever of the push button switch, and a substantially Z-shaped driving pin arranged for engagement with the heart cam groove during movement of the manipulation lever. This known type of alternate action mechanism is described, for example, in the specification of the U.S. Pat. No. 3,732,386.
In order to ensure safe alternate action of such a switch, the heart cam groove is required to have a suitable size. For instance, as disclosed in the specification of the U.S. Pat. No. 3,624,328, the heart cam is apt to have a width greater than the width of the outer end of the manipulation lever. Therefore, any attempt for reducing the width of the push button switch is often restricted undesirably by the necessary width of the heart cam groove.